OVERVIEW OF THE IMPACT OF MINING ON THE ... - IIED pubs

5.4.1.3 Pedology, agriculture and land use
Soils in the sub-catchment can be divided into six main groups:
• Shallow to moderately deep sandy-clay loam soils on flat and undulating terrain overlying rocks of the Ecca
Group, principally shales and silicified sandstones, in the western reaches of the catchment;
• Deep, black, blocky vertisols of the Springbok Flats in the south-western and western regions;
• Moderate to deep sandy loam soils lining long stretches of the Olifants River valley in its middle reaches;
• Shallow, sandy to sandy loam soils overlying granitic rocks of the Lebowa Granite Suite in the south-eastern
portions of the sub-catchment;
• Moderate to deep clay loam soils over much of the lower portions of the sub-catchment (located away from
the river channels), overlying the more porous unconsolidated sedimentary material; and
• Moderately shallow to moderately deep, clayey loam to clay-rich, fine-grained soils over granitic areas in the
lower reaches of the sub-catchment.
Most of the soils are suitable for commercial agriculture when sufficient water is available. Virtually all of the
areas with suitable soils, particularly the area downstream of the Loskop and Arabie dams, are contained within
the jurisdiction of formal irrigation boards or Government Water Control Areas. Further away from the main river
channels, land use is given over to small- and medium-scale livestock farming operations. A relatively wide
variety of crops are produced on the irrigated and rain-fed areas, primarily maize, wheat, sorghum, cotton,
tobacco, lucerne, potatoes, vegetables, sunflowers and soya bean. Large-scale citrus estates and sub-tropical
fruit orchards are located in the northern (e.g. Zebediela Estate) and north-eastern portions of the subcatchment.
The black vertisols of the Springbok Flats area are highly productive and most irrigation water is
provided from high-yielding boreholes. This region is perhaps the most economically important agricultural area
in the sub-catchment.
Large areas of the former Lebowa are given over to small-scale cattle ranching and the raising of goats and
donkeys. Much of the stock-rearing area in the central portions of this sub-catchment has been heavily
overgrazed and soils erosion is very prevalent.
Several towns (e.g. Marble Hall, Roedtan and Lebowakgomo) and numerous smaller settlements and farming
communities are present in the upper and middle reaches of the sub-catchment. Population numbers and
density are greatest in the upper and central reaches of this sub-catchment and decline somewhat towards the
downstream reaches. Some light industry is present in the towns of Marble Hall and Roedtan and these
industries are geared specifically to meet the needs of the extensive agricultural in the sub-catchment.
5.4.1.4 Surface water users
All the towns in the sub-catchment rely on water supplied from the small and large water supply impoundments.
In contrast, most of the numerous settlements in the sub-catchment have to rely on water supplied from
boreholes, springs, and hand-dug wells or from run-of-river abstraction points. The large areas of irrigation
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